Combining Inferior Vena Cava Diameter and Right Atrial Volume Index with Pro-BNP in Assessment of Volume Status in Haemodialysis Patients

Abstract

1.1.Background: The need for a concept of dry weight derives from an awareness of the dangers of being fluid overloaded. Which reflected by strain on the heart also abnormal low fluid load is also harmful and it might be associated with unacceptable degrees of low blood pressure and consequently of ischemia of vital organs. To judge excess volume, there are no gold standards, but its assessment has been done using a variety of tools. Physical examination which based on patient’s interdialytic weight gain and clinical signs, the assessment of volume is made poorly by physical examination. The assessment of inferior vena cava (IVC) diameter and its collapse with inspiration have been the most commonly used echocardiographic techniques to assess intravascular volume. Right atrial volume index which is noninvasive echocardiographic tool for assessment of volume overload but not widely used due to lack of data about right atrial volume even in normal population. NT-pro BNP is one of natriuretic peptides which secreted mainly upon mechanical stretching of cardiomyocytes, Both BNP and NT-proBNP are eliminated during hemodialysis, but they show different behaviors depending on the chosen dialysis membrane. 1.2.Methods: The study was conducted on two groups group I include 20 ESRD patients maintained on regular HD three times/week, four hour/session which they subdivided into two subgroups. The 1st subgroup included ten patients using high flux dialyzers and the 2nd subgroup included ten patients using low flux dialyzers. Group II: include ten healthy subjects as a control group. We estimate Urea, Cr, Hg and NT pro BNP by enzyme linked immune-sorbent assay (ELISA), trans-thoracic echocardiography stressing on inferior vena cava diameter and collapsibility index, right atrial volume index to the patients before and after HD and also in 2nd group. 1.3.Results: There was statistical significant difference between the pre HD and post HD in mean BP, Rt. at volume index, IVC diameter, and IVC collapsibility index. There were statistical significant difference between the Pro BNP low flux in pre HD and post HD, the Pro BNP high flux in pre HD and post HD. 1.4.Conclusion: Mean BP, Rt. at volume index, IVC diameter and pro BNP high flux were significantly decreased post HD session, and IVC collapsibility index, and proBNP low flux were increased post HD. So we can combine these parameters for effected evaluation of dry weight.